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    <meta charset="UTF-8">
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    <title>Document</title>
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<body>
    <script>
        function getSum () {
            var sum = 0;
            for (var i = 0;i < arguments.length; i++) {
                sum += arguments[i];
            }
            return sum;
        }
        console.log(getSum(1, 2, 3));
        console.log(getSum(1, 2, 3, 4));
        console.log(getSum(1, 2, 3, 4, 5));

        function getWord () {
            var str = '';
            for (var i = 0;i < arguments.length; i++) {
                str += arguments[i];
            }
            return str;
        }
        console.log(getWord('h', 'e', 'l', 'l', 'o'));
        console.log(getWord('w', 'o', 'r', 'l', 'd'));
    </script>
</body>
</html>